Fabrication, nanostructure evaluation, 3D electrical transport and electrochemical capacitance of PEDOT–Ti(IV)-doped iron(III) oxide nanocomposite

Poly[3,4-(ethylenedioxy)thiophene] (PEDOT) nanocomposites (NCs) reinforced by varying titanium(IV)-doped iron(III) nano oxide (NITO) particles have been fabricated in dodecylbenzene sulphonic acid by in situ polymerization process using ammonium perdisulfate as initiator. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, electron microscopy, BET surface analysis etc. followed by subsequent evaluation of thermal properties, temperature-dependent 3D electrical transport. Thermal stability of the NCs increased with increasing NITO amount in PEDOT matrix. Electrical conductivity of the NCs increased significantly with increasing NITO content (0.45–67.73 S cm⁻¹) and also with the temperature (50–300 K). 3D variable range hopping conduction mechanism explained the conduction pathways. Specific capacitance of NCs are enhanced with higher NITO content in polymer from 107 F g⁻¹ (pristine PEDOT) to 158 F g⁻¹ (NC) owing to the development of mesoporous (pore size: 4.1 nm and cylindrical pore volume: 0.103 cm³ g⁻¹) structure and high specific surface area (~104 m² g⁻¹).